The act of trying to imitate Robert De Niro's most famous facial expression. Can be used in situations when someone is accusing you of something, and you find the accusation to be absurd or preposterous.

Mother: "Where have you been?!"

Boy: *De Niro Face* "What? Are you talking to me? You have no goddamn right to question me, bitch! Get your god damn ass in bed before I beat your fucking head in!"